Loop taker with needle guard



April 28, 1959 JOHNSON 2,883,953

LOOP TAKER WITH NEEDLE GUARD Filed Nov. 21, 1956 I4 1 ll 37 35 V Fig.5

IN VEN TOR. v Ralph E; Johnson WITNESS MQ A M 4% A TTORNE Y United States Patent LOOP TAKER WITH NEEDLE GUARD Ralph E. Johnson, Mountainside, NJ., assignor to The Singer Manufacturing Company, Elizabeth, NJ., a corporation of New Jersey Application November 21, 1956, Serial No. 623,564

2 Claims. (Cl. 112-228) This invention relates to lock-stitch sewing machines of the type wherein a rotary loop-taker cooperates with a reciprocal needle in the production of lock-stitch seams. In such machines the rotary loop-taker is usually disposed beneath a flat work-suppcrting plate which is pro vided with an aperture to receive a substantially vertically disposed needle which is adapted to be reciprocated within such aperture for the purpose of cooperating with the loop-taker. In descending the needle passes in close proximity to the beak of the rotary loop-taker and on its up stroke the needle throws out a thread loop which is entered by the beak after which the beak carries the needle-thread loop about a lower thread mass which is carried by a bobbin supported within the confines of the rotary loop-taker. In the event that the needle is bent or deflected by a cross seam or any other irregularity in the material being sewn it may during its descent strike the loop-taker beak with the result that the beak is scored or otherwise damaged or in the alternative the needle may be broken.

It is the purpose of the present invention to provide a rotary loop-taker with a needle guard to guide the vertically reciprocating needle so as to maintain the needle out of the path of the advancing beak thereby to prevent damage to either element.

It is a more specific purpose of the present invention to provide such a needle guard on a rotary loop-taker of the type which rotates about a substantially vertically disposed axis and has its loop-taking beak disposed within the confines of the loop-taker body so as to cooperate with a substantially vertically reciprocatory needle which descends into the confines of the rotary loop-taker body.

With the above and other objects in view, the invention comprises the devices, combinations and arrangements of parts hereinafter described in connection with the accompanying drawings which illustrate a preferred embodiment of the invention from which the several features of the invention and the advantages obtained thereby will be readily understood by those skilled in the art.

In the drawings,

Fig. 1 represents a vertical sectional view taken through the base of a lock-stitch sewing machine which incorporates therein the present invention.

Fig. 2 represents, on a smaller scale, a top plan view of a portion of the rotary loop-taker disclosed in Fig. 1.

Fig. 3 represents a bottom plan view of the rotary loop-taker disclosed in Fig. 2.

Fig. 4 represents, on an enlarged scale, a fragmentary vertical sectional view of a portion of the rotary looptaker and illustrating the use of the present needle guard for the purpose of preventing t1 2 needle from engaging the loop-taker beak.

Fig. 5 represents a fragmentary View of a proportion of the rotary loop-taker and illustrating the manner in which the needle guard is disposed within the loop-taker body.

The present rotary loop-taker represents a modified version of that loop-taker which is disclosed in my copending US. application Serial No. 471,766 filed November 29, 1954.

Referring particularly to Fig. 1, the present invention is adapted to be incorporated in the base portion of a sewing machine formed with a work-supporting platform 9 having a throat-plate 10 formed with a needlereceiving aperture 11 and feed-dog clearance slots 12 as Well as with a conventional slide plate 13 which, when shifted in a right-hand direction, gives access to a rotary loop-taker mechanism generally designated by the numeral 14. Cooperating with the loop-taker 14 in the formation of lock-stitches is a conventional thread-carrying needle 15 mounted within a needle-bar 16 which is actuated in the usual manner so as to reciprocate in a direction substantially lengthwise of the needle 15.

Extending through the feed slots 12. and over the looptaker 14 is a feed dog 17 carried by a feed bar 18 which is actuated in a manner such that feed dog 17 will during the operation of the machine feed work from right to left over the work-supporting member 9. From this is to be understood that the rotary loop-taker 14 is disposed substantially in front of the feeding mechanism as Well as in front of the reciprocatory needle 15 so that the operator may have ready access to the looptaker mechanism.

The present rotary loop-taker is formed with a shaft 19 supported within a bearing member 20 formed in the lower sewing machine frame. The lower sewing machine frame is provided with a rotary shaft, not herein shown, which is geared to the substantially vertically disposed loop-taker shaft 19 for the purpose of rotating the loop-taker in a counterclockwise direction as viewed from above. The bearing member 20 is provided with a shoulder 21 adapted to support the loop-taker which is in tegrally formed with the shaft 19. More specifically, the lower portion of the loop-taker is provided with a seat 22 which engages the top portion 21 of the bearing member 20.

The present rotary loop-taker has cooperating with it an inverted U-shaped member 23 disposed in straddling relation with the loop-taker and with one limb of the member disposed outside of and supported beneath the loop-taker on a base portion 24 which in turn is mounted on the support 20. The other limb of the member 23 is disposed within the confines of the loop-taker ad-' jacent the loop-taker thread case generally designated by the numeral 25 and provides a substantially horizontally disposed thread supporting bar 26 from which projects upwardly an abutment member 27 which functions to engage a portion of the thread case thereby to prevent the thread case from shifting in a clockwise direction. For further details concerning this structure reference may be had to my above noted copending application Serial No. 471,766.

The present loop-taker comprises a substantially cupshaped body including a bottom wall 28 and an annular side wall or a ring 29 extending laterally from the periphery of the bottom wall. The side wall 29 is provided with an interior circular wall 30 formed concentrically with the vertical axis of the loop-taker rotation which, of course, coincides with the longitudinal axis of the looptaker shaft 19. As is particularly illustrated in Fig. 2, the side Wall 29 is provided with a gap 31 in the form of a scarf-like narrow channel which cuts through the interior wall 30. The annular loop-taker side wall 29 is also provided with an interior circular rib 32 having a gap therein coinciding with the interior wall gap 31 to provide at one end and as a part of such rib a loop-seizing beak 33 which is disposed closer to the center of the ring than and in substantial overlapping relation with the other end portion 34 of the rib. From this, it is to be underaeeagss stood that the gap 31 forms a scarf-like narrow channel which cuts through the interior wall 30 and the rib 32 to form two bias-cut overlapping end portions of the ring and an internal loop-seizing beak 33 at one end of the rib 32. As shown in Fig. 1, the rib 32 and wall 30 supports the thread case 25.

The thread case 25 is provided in the usual manner with a threadcarrying bobbin not herein shown, which bobbin carries a lower or bobbin thread.

Referring particularly to Fig. 2 the loop-taker beak 33 is disposed over a needle-receiving aperture 35 formed within the bottom wall 28 of the loop-taker so as to receive the needle on its down stroke in a manner as is best disclosed in Figs. 1 and 4.

The present rotary loop-taker is provided with a needle guard in the form of a needle-engaging wall surface 36 carried by the bottom wall 28 at a location substantially beneath the loop-seizing beak 33 and facing toward the center of the loop-taker body so as to deflect the needle toward the center of the loop-taker body and away from the beak 33 thereby to prevent damage either to the needle or to the beak 33 in the event that the needle is bent or deflected from its proper position.

More specifically, the needle-engaging Wall surface 36 is provided upon an elongated bar 37 which is disposed beneath the beak 33 and at one side of the aperture 35. As may be best seen in Figs. 3 and 5 the bar 37 is adapted to be received within slots 38 and 39 formed in the bottom and side walls 23 and 29 of the loop-taker body. The bar 37 may be secured within the slots 38 and 39 by soldering, welding or by the use of an appropriate adhesive material. In this position the wall 36 can engage the point of the descending needle 15 and deflect the latter out of the path of the rotary beak 33 in the event that the needle is bent or otherwise deflected out of its proper position. As may be observed from Fig. 2 the wall 36 may be formed as a concave surface disposed nearer the center of annular ring 29 than the beak 33.

From the foregoing it is manifest that the present invention provides a simple and efiicient means for preventing injury to the complemental stitch-forming mechanism of the lock-stitch sewing machine by a bent or deflected needle as well as for protecting the needle itself against breakage. Those skilled in the art will readily appreciate that the present needle guard not only provides an eflicient means for accomplishing its avowed purpose but at the same time it is designed in a manner such that it can be most inexpensively manufactured and applied to a lock-stitch sewing machine.

Having thus described the nature of the invention, what I claim herein is:

1. A rotary loop-taker for sewing machines having a reciprocatory thread-carrying needle, comprising, a cup-shaped body including a bottom wall and an annular side wall extending laterally from the periphery of the bottom wall, the bottom wall having a slot formed therein, an interior loop-seizing beak extending inwardly from the peripheral edge of the side Wall so as to engage the thread loop presented by a needle disposed within the confines of the annular side wall, and a needle-guard in the form of an elongated bar carried within the slot of the bottom wall at a location substantially beneath the loopseizing beak and providing a wall surface facing toward the center of the loop-taker body so as to deflect a needle toward the center of the loop-taker body and away from the beak.

2. A rotary loop-taker for sewing machines having a reciprocatory thread-carrying needle, comprising, a cupshaped body including a bottom Wall having a needlereceiving aperture flanked on its opposite sides with a pair of aligned slots, and an annular side wall extending laterally from the periphery of the bottom wall, an interior loop-seizing beak extending inwardly from the peripheral edge of the side wall and over the bottom wall aperture so as to engage the thread loop presented by a needle disposed within the confines of the annular side wall, and a needle guard in the form of an elongated bar carried within the slots of the bottom wall so as to span the bottom Wall aperture at a location beneath the loopseizing beak, the bar providing a wall surface facing toward the center of the loop-taker body so as to deflect a needle toward the center of the loop-taker body and away from the beak.

References Cited in the file of this patent UNITED STATES PATENTS 494,039 Speight et al. Mar. 21, 1893 845,092 Jacob et al. Feb. 26, 1907 2,019,284 Wesson Oct. 29, 1935 r refiis. 

